EasyTAG

http://easytag.sourceforge.net/
EasyTAG is an utility for viewing, editing, and writing tags for your MP3, MP2, Ogg Vorbis, and FLAC files using a nice simple GTK+ user interface. Features include (among others):

View, edit, write MP3, MP2, FLAC (supporting ID3v2 and ID3v1.x
specifications) and Ogg Vorbis tags
Auto tagging: parse filename and directory to automatically complete
the fields (using masks)
Ability to rename mp3 file from tag (using masks)
Can process all the files in a selected directory
Ability to browse subdirectories
Recursion for tagging, removing, renaming, saving
Can set a field (artist, title,...) to all other files
Reads and displays file header information (bitrate, time, etc.)
Auto completion of the date if partial information is entered
Can undo last changes
Can process fields of tag and file name (convert letters into
uppercase, lowercase, ...)
Loads files for character translation
Tree based browser
List to select files
Simple and explicit interface
Menu bar and shortcuts
Displays messages in status bar
French, German, Russian, Dutch, Hungarian, Swedish, Italian and
Japanese and Ukranian translations

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